Heating of fluids



Aug w. c. HENSEL v 2,355,800

- r HEATING OF FLUID v Filed April 20, 1942 2 Sheets-Sheet 1 INVENTOR WALTER C. HENSEL j ATTORNEY Aug. 15, 1944.

2 Sheets-Sheet 2 FIG.

INVENTOR WALTER c. HENSEL' ATTORNEY I Patented Aug. 15, 1944 *'umreo 's iArizs PATENT OFFICE 'versal Oil Products Company, Chicago, 11]., a

corporation of Delaware Application April 20,1942, Serial No, 439.737

Claims. (01.122-510) I lustrate one of the manyforms of apparatus em- This invention relates to improved-supporting means for tubular heating elements and more particularlyto a supporting means for tubular elements. which are subjected to high rates of,

heating.

More specifically, this invention relates to tubular heating element supporting means having passageways therethrough which are open at opposite ends to the atmosphere and the combus-w loy steels, such as those containing chromium and nickel or high temperature cast irons, such as Meehanite. There are,- however, maximum allowable temperatures to which these materials may be subjected and still retain the physical characteristics necessary to prevent their failure or distortion. The trend in modern heater designs, especially in the oil refining industry, has

been toward steadily increasing rates of heat input to the fluid conduit. This is accomplished by locating the fluid conduit within the combustion zone of the furnace wherein it is exposed .to high, rates of direct radiant heat. The design of suitable supporting means for such fluid conduits has become an ever increasing difficulty but may be overcome by employing the present invention.

Heretofore a satisfactory answer to the problem of supporting fluid conduits located in such extremely high temperature zones has not been disclosed, There are various known means for cooling the main structural members of the support, but no means have been provided for cooling those portions of the support which are 10- cated in the hottest part of the heating zone and whose function is important in supporting and retaining -the individual tubular elements of the fluid conduit in their desired locations. The present invention provides means'for cooling substantially the'entire fluid supporting member and especially those portions of said member which are subjected to the highest temperatures and which would normallybe the first to fail due to. overheating.

, 'll ieaccginpanying diagrammatiadravtingsilintroduced through ports I! in floor 5 to the com air may be regulated by adjusting the relationshipbodying thejeatures of the invention and it and a subsequent description thereof are included in this specification in order that the features and advantages of the invention may be more clearly understood.

Fig. l of the drawings illustrates, principally in section, a crossfsect-ional elevat onal view of one form of heater embodying the features of the invention.

Fig. 2 illustrates an enlarged elevational view of one of the supporting members with a portion cut'away to show the interior construction.

Fig. 3 is a view of the member shown in Fig. 2- taken from a plane indicatedby line 3-4.

Fig. 4 illustrates a sectional plan view of a modified arrangement of the tube support shown in Figs. 2 and 3 with insulation added to its exterior surface.

herein illustrated and generally referred to as a center wall updraft heater is comprised of com-' bustion and heating zones land I which are located on opposite sides of vertical center wall 2. Combustion and heating zones i and i are defined by the side walls 3 and 3', end wall 4 and its opposing end wall not shown, and the floor 5, all

of which may be made up of satisfactory refractory materials of monolithic or built-up construction. The upper portions of walls 3 and 3' converge toward the center 'to form a zone of restricted cross-sectional area 6 directiy above the center wall 2. Buck stays I are provided adjacent the outer walls of the heater to act as supporting means therefor and the entire heater may be supported on the foundation 8. The entire heater may be enclosed by a sheet metal shell l3 secured to the outer flanges of buck stays 1 thus providing air spaces 22 between said she'll andthe walls 3 and 3'. Suitable burners 9 supplied through conduit III with, in this case, gaseous fuel regulated by valve Ii are disposed below the floor 5. Air for combustion will be drawn through louvres I4 and be directed in a downward direction paralleling the buck stays I by the draft action of the stack. The desired combustible mixture of fuel gas and air will be accomplished in mixer l5. and said mixture will be bustion zones of the heater. Any desired excess between burner nozzles l6 and ports i2.

Adjacentthe vertical walls I and I and the sloping portions thereof in the heater here illustrated are disposed at rowof parallel tubular heating elements If. It is, of course, entirely within thescope of the invention to employ more than a single row of heatingtubes adjacent the walls. In the restricted section of the heater there is a double row of tubes l8 which are disposed in staggered arrangement; Tubes i1 and I! are located substantially within the combustion zone of the heater and are subjected to high rates of heating and it is the purpose of the invention to provide supporting means therefor. It is the general practice in heaters of this type to provide a plurality of tubular elements in the space located directly above the tubes 18 but as this is a relatively cooler zone, tube supporting means for these elements have not been a great problem and, therefore, to simplify the drawings these tubes are not shown. Tubes II are supported by means of a plurality of members i9 which castings provided with openings 2| which provide means of communication between the air space 22 and the interior of said members. Small ports or weep holes 23 are provided in the proiecting portions 24 of the member ID and furnish means of communication between the interior of said members and the combustion zone of the heater. Tubes I! are supported fromthe buck stays by means of a substantially hollow member 25. Member 26 is provided with ports 28 and small orts 21 in communication with the air space 22 and interior of the heater, respectively. 231d is secured to the buck stays by suitable bolts In cases where extremely high temperatures are generated within the heater, suitable insu-,-

-'lation may be applied. to the exterior surface of the members, as shown in Fig. 4. This insulation 2! maybe retained in place by the'lugs 20 attached to the supp rting member, for example, as illustrated in my recently issued Patent No. 2,270,297.

when the heater is in operation, the pressure differential between the atmosphere and thefinterior of the heater will induce a flow of air through the several supporting members thereby causing the cooling thereof and preventing their failure due to overheating. I I

I claim as my invention:

1. In combination with a furnace, walls form'- ing a combustion and heating zone, heating tubes within said zone adjacent one of the furnace walls, a hollow supporting member projecting through-the last-named wall and communicating with the atmosphere outside the furnace, recesses in said member for receiving said tubes, a port in said member opening into the interior of said combustion and heating zone, and means for inducing the flow of air through said member into said zone.

. 2. In combination with a furnace having a vertical wall and a horizontal heating tube within the furnace adjacent said wall, a hollow supporting member projecting through said wall and communicating with the atmosphere outside the furnace,- said member being recessed to receive said tube, a port in said member opening into the interior of the furnace, and means for inducing the flow of air through said member into the furnace.

3. In combination with a furnace having a vertical wall and a plurality of vertically spaced horizontal heating tubes within the furnace adjacent said Well, a hollow supporting member projecting through said wall and having an opening outside the furnace, additional openings 'in said member in the portion thereof disposed within the furnace, said member being provided with vertically spaced recesses to receive said tubes, and means for inducing the flow of air through said member from the first-mentioned opening to said additional openings.

- 4. Incombination with a furnace having horizontal heating tubes therein, a hollow member projecting through a wall of the furnace and having a recessed portion adapted to engage and support at least one of said tubes, said member being provided with an opening outside the furnace and an opening within the furnace, and means for inducing the flow of air through said member from the first-mentioned opening to the second-mentioned opening.

-5. In combination with a furnace having horizontal heating tubes therein, a hollow member projecting through a wall of the furnace and having recesses for supporting a plurality of said tubes, said member being provided with an opening outside the furnace and additional openings within the furnace adjacent the tube supporting recesses, and means for inducing the flow of air through said member from the flrstqnamed opening to said additional openings.

WALTER c. HENSEL. 

